Stamp-mill.



PATENTED APR. 4, 1905),

A. MOOGMBIE.

STAMP MILL.

APPLIOATIOIT FILED NOV.B,1904.

Patented April 1905.

ALEXANDER MOGOMBIE, OF GRASS VALLEY, CALIFORNIA, ASSIGNOR OF ONE-HALF TO JAMES MOCOMBIE, OF CHICAGO, ILLINOIS.

STAIViP MlLL.

SPECIFICATION formingpart of Letters Patent No. 786,590, dated April 4, 1905. Application filed. November 8, 1904. Serial No- 231,887.

To (LZZ 70/1/0111 it nm/y concern:

Be it known that I, ALEXANDER MoConBIn, acitizen of the United States, residing at Grass Valley, in the county of Nevada and State of California, have invented new and useful Im provements in Stamp-Mills, of which the following is a specification.

My invention relates to improvements in crushing-mills of that class in which a rising and falling stamp is operated so as to drop upon the rock or material, which may be fed to and contained in a mortar having the usual dies between which and the-stamp the rock will be crushed.

The invention consists in a means for rapidly reciprocating the stamps, a means for rotating them, and in details of construction which will be more fully explained by reference to the accompanying drawings, in which- Figure 1 is a side elevation of my improved stamp-mill in partial section. Fig. 2 is a rear elevation of same. Fig. 3 is a plan view showing mechanism for turning the stamps synchronously with their reciprocation.

In the ordinary construction of stam p-mills it is customary to raise the stamps by means of cams fixed upon a horizontal revoluble shaft, these cams engaging tappets upon the stamp-stem, and when the point of the cam passes from beneath the tappet the stamp is allowed to drop. The friction of the sliding cams upon the tappets and other frictional resistance greatly increases the power necessary to drive a line of stamps, and the speed at which the stamps may be made to drop is also quite limitedf In my invention 1 design to reduce the frictional resistance and to increase the rapidity with which the stamps may be reciprocated.

As shown in the drawings, A represents a mortar having screens for the discharge of the crushed material when it is reduced to a sufficient iineness, this mortar being of any usual or suitable. construction.

2 represents a framework or support for the mechanism at the upper part of the apparatus, and 3 represents guides through which the stem 4: of the stamp is slidable.

may be of any suitable or desired size and 5 weight and may have the usual or any desired form of shoes adapted to crush the ore be tween themselves and the dies within the mortar. These being common and well known are nothereshown. The upperendofeachstampstem has a swiveled link 5, turnably fixed in its end, and to this link is connected a rope 6, which passes over a vertically-adjustable pulley '7, which either has its shaft suitably journaled in the upper part of the frame 2 or the pulleys may each have hubs of su tiicient length turnable upon a stationary shaft.

8 is a crank-shaft journaled upon the frame, as shown, and may have a pulley, as at 9, or other equivalent means for transmitting power 5 to rotate the shaft. 1 have here shown the apparatus as comprising two stamps, and the crank-shaft has opposed cranks, one for each stamp. -A loosely-turnable box 10 is fitted upon each of the cranks, and the ends of the 7 ropes 6 are connected with these boxes, so that when the crank-shaft is revolved the ropes will be alternately pulled by the action of the cranks, and thus the stamps will be raised by the pull upon the ropes and allowed to descend by the return upward movement of the cranks. The revolution of the crank-shaft may be made as rapid as possible within the limitations of gravitation to cause the stamps to drop properly between the pulls upor. the ropes by which they are raised, and thus the power is applied directly to the stamp and with only the small amount of frictional resistance due to the shaft and crank journals. If the speed of the cra1'ikshaft is not suflicient 5 to slacken the ropes, it will be seen that the weight of the descending stamp will assist to raise the one which is being lifted, and it will be preferable tokeep the speed within such a limit that the ropes will be kept substantially 9 taut. By this construction there is less noise, less friction, and comparatively little power is required to operate it.

In order to rotate the stamps step by step during the operation, which is always desir- 9F able, 1 have shown each stamp-stem having a key or feather, as at 11, slidable through a The stamp 1 ratchet-wheel12, which ratchetwheel is turnably supported contiguous to the box in which the stamp-stem slides.

13 represents spring-pressed pawls, here shown as having a common pivot upon a lever 14, which is pivoted intermediate between the stamp-stems, as plainly shown in Fig. 3.

i5 is a suitably-fillerumed lever having a pin 16 or equivalent device engaging the end of the lever 14. The lever 15 has at its outer end a roller or equivalent antifrietional device adapted to engage a cam 17, which cam is fixed upon the crank-shaft and is revoluble with it. The action of this cam upon the lever 15 will cause said lever to move from side to side, and through this lever the lever 14: is also reciproeated, carrying with it the pawls 13. Thus each of the pawls will alternately engage with the ratchet 12 of one of the stampstems and will act to turn the stamp a short distance at each reci n'ocation, thus presenting the faces of the stamp-shoe, so as to equalize the wear thereon. The turning of the l l l l i staum-stcin. takes place at the end of each downstroke. The turning of the stamps at this time also acts to grind the ore between the shoes and dies.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. In a stamp'mill, vertically-guided stamps and stems, a crank-shaft, ropes connecting with the cranks, direction-pulleys over which the ropes pass, turnable connections between the ropes and the stamp-stems, and means including a pivoted lever and connection operated from the crank-shaft for intermittently training the stamps during their reciprocation.

2. Inastamp-mill, vertically-guided stamps 1 and stems, a journaled revoluble crank-shaft, ropes having one end connected with the cranks, pulleys over which the ropes pass, turnable connections between the other ends of the ropes and the stamp-stems, ratchet-wheels through which the stamp-stems are movable, with feathers engaging the ratchets and stems,

and reciprocating pawls whereby the ratchets rocating stamps, a crank-shaft, flexible ropes connecting with the cranks and turnable connections upon the stamp stems, ratchets through which the stems are slidahle and teeth ers turnably connecting the stems and ratchets,spring-pressed pawls engaging the ratchet teeth, a lulcrumed lever upon which said pawls are pivoted, a second 'fulcrumed lever, means engaging the two levers, a cam carried by the crank-shaft with which cam the lever engages, and by the movement of which the pawls alternately engage and move the ratchets.

in testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.

ALEXANDER McCOMBlE.

Witnesses:

CHAs. Bowen, M. OUoNnnLL. 

